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Topic: Thinking I need some solar! (Read 1674 times)

We don't do a lot of boon docking but recently had an experience that changes how I view being "off the grid"' We spent a total of 7 days without benefit of hookups. 5 of them were on the Rincon Parkway in Ventura, CA I had a little over a 1/2 tank of fuel but after 4 days I guess I had drawn the fuel down to 1/4 tank and the generator would not run. Had to stow everything away and drive off to get some fuel and return. We were running the genset about 3-4 hours a day. We have a residential fridge and did watch a little TV.

Would really like recommendations as to how much solar I might need to either eliminate the genset all together or drastically reduce its run time. I'm thinking a couple of roof mounted panels. Any thoughts would be appreciated.

I have solar on both my RV and my boat - LOVE IT! I would recommend you put as much on top as you can fit/afford. Some people will tell you not to get solid residential style panels because they can't handle the vehicle - nonsense. They are the most efficient panels you can get. As I said, I have them on my boat and RV and have not had a single problem with any of them. By far the most important part of the system is the controller. Don't go cheap - buy an MPPT controller. You will be glad you did.

One caveat on "how much" - if you have a very small battery bank (like 2 golf cart batteries or something), don't go overboard. It will be a waste of money to put 1500 watts on that small of a battery bank.

Four 225 watt panels and four 200 amp hour batteries let us be independent of outside power. But, are you willing to spend $2500 for "not a lot of boondocking?" You can buy a lot of fuel for that kind of money.

I'll give you my personal experience with RV solar. We rely primarily on solar power while boondocking - and most of our camping is boondocking. Our coach came with a 22 CF res-fridge, a 2800 watt inverter, three entertainment centers and all the lights have been converted to LEDs. It's a relatively high consumption RV. It also came with six AGM house-batteries. Most of our boondocking is in the California and Arizona deserts, so there's usually a lot of sun. (Makes a big difference)

Before I installed solar, we were having to run our 10K generator nearly four hours a day to keep the batteries charged. I grew tired of that fast, so I installed 960 watts of flat-mounted solar panels. On a sunny day, our batteries were fully charged by about 12:00 to 12:30. The panels would keep the batteries charged until about 3:30, at which time our consumption (primarily the fridge and inverter) would start to draw the batteries down. I had also installed a Trimetric RV 2030 battery monitor so I could see the discharge rates.

In the morning, our battery power was regularly down to about 60%, which I didn't like. Routinely drawing batteries down that far can shorten their lives, and those are pricey batteries. I installed two more identical house-batteries, for a total of 840 AH, and that did the trick. Now they're usually at about 75 to 80% in the morning, which is plenty of power to run our 12 cup coffee maker and nuke something in the microwave.

The bottom line is, as long as there's adequate sunlight, we don't have to run our generator at all - unless we want air conditioning. Solar is definitely a balancing act between power generated, power used and the ability to store it. Another thing I did that really helped was to make our panels tiltable. Tilting them toward the sun in the winter months has incresed their output by about 40%. That translates to faster charging, as well as longer charging.

Solar discussions can and will go on forever it seems. The more/better equipment youinstall on your rig probably depends on the amount of dough you want to spend. To me its like a boat or truck engine. I believe in having plenty of power with me in case I ever need it. You never know what circumstances await you, especially boondocking. I just added my 5th AGM battery along with 4 100 watt panels on the roof. Can't wait to see how this performs. Nothing better than being out in the quiet still air of my campsite!!!!

MHO there is no sense going solar to replace a power hungry RV or RVer's. You must do without conveniences to truly reap the cost benefits. It's like a life style choice. My 300watt 350 amp hour 1200w inverter system, self installed was $1300. Not your high end big name equipment ether. I'm happy to get 10 hours of 5 amp/120v usage

I'm afraid you lost me on that one Wireman. Are you saying that a 300 watt solar setup that meets the power requirements of one RV/RVer is acceptable, but larger systems for larger RVs aren't, or are you saying that RVers should do without some amenities while boondocking?

One of the benefits of solar, even though you might not have enough to keep from running the generator, is that a good solar controller will have a max voltage adjustment to allow you to fully charge your batteries whereas there are converter/chargers that dont put out enough voltage to fully charge the batteries. For instance, I have a Progressive Dynamics PD9260 charger/converter to charge my batteries when running the generator or shore power, but the max charge voltage is only 14.4 volts which is not enough to fully charge most wet cell deep cycle batteries as Trojan T-105s in series to make 12 volts require 14.8 volts to get fully charged, and some Interstate 6 volts in series to make 12 volts require 15.3 volts to get fully charged.

I'm afraid you lost me on that one Wireman. Are you saying that a 300 watt solar setup that meets the power requirements of one RV/RVer is acceptable, but larger systems for larger RVs aren't, or are you saying that RVers should do without some amenities while boondocking?

Kev

No don't you do without. Spend $5,000-$10,000 on your solar. Then still run your generator to power what it won't. If you insist on solar only you will have to do without or maybe clad the Class A in PV with 2000 ahr battery bank then have at it with all those sunny days down there. Solar is a supplement in a RV platform. To the OP for your usage I'd say 600watt of panels paired with 6- 6 volt GC batteries (300 ahr usable) into a 2000w inverter and hope you have 5 hours of solar noon every other day or so.

Informative article. Wonder if there are businesses specializing in rv solar setups. Would sure like to pull into one on the West Coast and have a pro make recommendations. Will have to do a google search. Thanks for the responses.

Informative article. Wonder if there are businesses specializing in rv solar setups. Would sure like to pull into one on the West Coast and have a pro make recommendations. Will have to do a google search. Thanks for the responses.

Just because a place may list themselves as professional solar installers, doesnt necessarily mean that they will sell and install an optimized system for you.

The more you know about solar and what you need, will go along way in getting a good system at a fair price.

No don't you do without. Spend $5,000-$10,000 on your solar. Then still run your generator to power what it won't. If you insist on solar only you will have to do without or maybe clad the Class A in PV with 2000 ahr battery bank then have at it with all those sunny days down there. Solar is a supplement in a RV platform. To the OP for your usage I'd say 600watt of panels paired with 6- 6 volt GC batteries (300 ahr usable) into a 2000w inverter and hope you have 5 hours of solar noon every other day or so.

At the risk of sounding argumentative, which is not my intent, I think it's important to provide people with accurate information when they ask about RV solar, because it's an often misunderstood topic. Exagerating the costs, benefits or drawbacks of RV solar only adds to the confusion.

There are articles all over the internet, that have been written by "so called" RV solar experts, that contain distorted and inaccurate information. Depending on what someone's trying to accomplish with solar, it can get expensive, so becoming educated on the facts is important to accomplishing your own goals as well as saving money.

There's certainly no "one size fits all" solution to RV solar, and it's often difficult to use rules of thumb. That's because there are so many variables that will affect how effective solar will be. What works well for one person in one location, may not work well for someone else who's camping in another state - even with the same RV. Where and when someone camps, their average power consumption, their battery capacity and when they use high consumption appliances, will all impact how well solar is going to work for them.

Many RVers rely primarily on solar power to charge their batteries, and a lot of them don't even have a generator. That would be a bit tenuous for us, but if it works for them, great. I've always had the same opinion as Wireman - that solar is more of a supplimental power source for RVing, but the fact is, in our last five boondocking trips, which were each several days long, we've put less than one hour on our generator (total, for all five trips).

Our residential fridge ran 24 hours a day, we ran our microwave, coffee maker, TVs, chargers etc. day after day, night after night, whenever we wanted to, all off our inverter and batteries - batteries that were recharged almost exclusively with solar power. So which power source was supplimental?

You don't need a 200O AH battery-bank or an RV clad in solar panels to accomplish that, and it certainly doesn't have to cost $5000 to $10,000. We do it in a relatively large RV with an 840 AH battery-bank, an MPPT controller and six 160 watt tiltable panels. We've even got room on the roof for more panels, we just don't need them.

I've always had the same opinion as Wireman - that solar is more of a supplimental power source for RVing, but the fact is, in our last five boondocking trips, which were each several days long, we've put less than one hour on our generator (total, for all five trips).

I think the problem is the residential refrigerator--those are not terrible compatible with boondocking. It can be done, but it's not ideal.

We have a 40-foot motorhome with 1,050 watts of flat-mounted solar and six golf-cart batteries (690 amp hours, I think). With the refrigerator on propane, we can go indefinitely on solar alone at this time of the year. We just spent April and part of May boondocking. We did three stints of two weeks each without running the generator (they kick you out for two days after two weeks, or we would have just stayed there the whole time and even then, we wouldn't have needed the generator).

Last winter, we did some boondocking in Phoenix and it was a little dicier on solar only, with our refrigerator on propane.

I've done some math and concluded that I wouldn't be comfortable trying to use a residential refrigerator on our amount of solar--it would have to be pretty ideal conditions, and you can't rely on that.

Not to dissuade anyone from adding solar--the only thing I hate more than listening to my generator is listening to someone else's. But people with residential refrigerators need to understand that it's a whole different ball game from people putting solar on RVs with propane refrigerators.

I agree. The typical factory installed residential fridge setup isn't well suited for boondocking - unless, of course, you enjoy listening to genset song. I haven't seen a factory installed setup yet that was capable of running the inverter and fridge for more than a day - some can't even do that.

Our last motorhome had an LP fridge, no inverter and a single 100 watt panel. As long as it was sunny, the only time we had to run the genset was when we wanted to run the microwave, coffee maker or air conditioner. Those LP fridges are well suited for boondocking.

However, by installing adequate solar and 30% more battery capacity, we were able to overcome the draw of our current motorhome's res fridge and inverter - as well as everything else in the coach. Now we have a large res fridge (which we love) and since the microwave and coffee maker run off the inverter, the only time we need to run the genset is if we want air conditioning, which isn't needed much in the winter months.

Yes, it cost some dough to achieve that capability, but we boondock quite a bit, and we don't like listening to our generator droning away, so it made sense to us. Res fridges do cause some power challenges when boondocking, but they can be overcome with some $$ and creativity.

Yes, it cost some dough to achieve that capability, but we boondock quite a bit, and we don't like listening to our generator droning away, so it made sense to us. Res fridges do cause some power challenges when boondocking, but they can be overcome with some $$ and creativity.

If you want to talk about dough, think about what we paid for our solar panels in 2005! For several years, our solar panels were the only appreciating asset we owned.

I know people love their residential refrigerators, but I kind of resent them. With solar being so cheap these days, it would be possible for lots more people to have it--maybe only enough to do like you used to and have to use the generator to run the microwave, but that's a lot better than using them for charging batteries.

But the goal line got moved with the popularity of residential refrigerators, and at just the point when we might have been moving away from generators somewhat, we're getting in even thicker because of the increased generator run time to support residential refrigerators, or the huge solar systems that people who aren't serious boondockers won't even consider.

So just when we might have seen an increase in solar and a decrease in generators, we might still be seeing an increase in solar but it's not necessarily bringing down generator use.

If you want to talk about dough, think about what we paid for our solar panels in 2005! For several years, our solar panels were the only appreciating asset we owned.

I know people love their residential refrigerators, but I kind of resent them.

LOL! Ain't that the truth! Solar has definitely come down in cost since then, and we were lucky to have been on the cheaper end of the spectrum.

I was kind of neither here nor there when it came to res fridges, but now that we've had one... OMG. And everyone I know of who has made the transition, feels the same way. Faster cooling, no flames, no fire hazard recalls, no leveling issues, larger storage... But you definitely have to deal with the power issue if you're a boondocker.

Hello, I haven't been on here in quite a while. We just purchased a new 2017 Sundance 22 ft travel trailer. We are exploring the solar options. Has anyone sucessfully ran their A/C unit on an inverter with solar panels and batteries? My friend is building his own teardrop trailer and he put a small residential a/c unit in it. He runs it off of a 5,000 watt inverter and a single deep cycle battery. He keeps telling me that I should be able to run my whole trailer including the a/c on about a 5 - 7000 watt inverter with some solar panels to recharge the batteries. I currently have 2ea 12 volt deep cycle batteries on my new trailer and no solar. The last time we went boondocking we ran a generator 3200 watt with 4000 peak and it ran the ac just fine. However, I am not the guy who wants to run it all the time. In fact when I finally turned it off I could hear someone cheering from another campsite along the river that we had finally shut it off. I would really like to know more about the solar option. I would be willing to spend up to 800 or 1000 bucks if I thought it would actually work but I don't know enough about it to make the jump just yet. I would really want it to be able to run the A/C as well as my dish network and 32" tv. Can anyone tell me if this is even possible? I know that my friends little trailer gets cool but it is only a few square feet since it is a teardrop trailer. It is easy for him to tell me I can do it but he can't even stand up or go to the bathroom in his trailer. I just want help to know if it is actually possible. Thanks, Mike (lions6)

I really don't mean to belittle your friend, but there are all kinds of problems with his opinions and recommendations. As a frame of reference, our 43 foot motorhome has a large residential fridge, three entertainment centers, a 12 cup coffee-maker and a large convection microwave oven. All of them run off a 2800 watt inverter. A larger inverter - especially one rated at 5000 to 7000 watts would be way overkill - a waste of power and money.

It is technically possible to power a single roof air unit with batteries and an inverter, but very impractical. Our eight deep cycle AGM house-batteries (840 AH) and inverter could probably do it for 30 minutes or so on a full charge, but then they'd be drained. Do that several times and the batteries would be toast. We'd also be out of power for everything else.

The charging rate of our 960 watt solar array could probably keep up with the draw of a single roof AC unit for a couple of hours, but only if it was sunny. There's no way our relatively large battery-bank, inverter and solar array could power even two of our three roof AC units for any length of time. The surge from the compressors kicking on would overload the inverter. A larger inverter would require a proportional battery-bank - one that most RVs wouldn't have enough room for. You're talkin' a BIG battery-bank!

Powering an RV's roof AC unit(s) with batteries and an inverter just isn't practical - even with a relatively large solar array. If it were, people would be doing it all the time. A generator is really the only practical solution.

Hello, I haven't been on here in quite a while. We just purchased a new 2017 Sundance 22 ft travel trailer. We are exploring the solar options. Has anyone sucessfully ran their A/C unit on an inverter with solar panels and batteries? My friend is building his own teardrop trailer and he put a small residential a/c unit in it. He runs it off of a 5,000 watt inverter and a single deep cycle battery. He keeps telling me that I should be able to run my whole trailer including the a/c on about a 5 - 7000 watt inverter with some solar panels to recharge the batteries. I currently have 2ea 12 volt deep cycle batteries on my new trailer and no solar. The last time we went boondocking we ran a generator 3200 watt with 4000 peak and it ran the ac just fine. However, I am not the guy who wants to run it all the time. In fact when I finally turned it off I could hear someone cheering from another campsite along the river that we had finally shut it off. I would really like to know more about the solar option. I would be willing to spend up to 800 or 1000 bucks if I thought it would actually work but I don't know enough about it to make the jump just yet. I would really want it to be able to run the A/C as well as my dish network and 32" tv. Can anyone tell me if this is even possible? I know that my friends little trailer gets cool but it is only a few square feet since it is a teardrop trailer. It is easy for him to tell me I can do it but he can't even stand up or go to the bathroom in his trailer. I just want help to know if it is actually possible. Thanks, Mike (lions6)

Does your friend have any experience with RV air conditioners? All you have to do is run the math on usage and batteries, and you will confirm what Kevin says. Even your relatively small trailer is probably 5x the volume of a teardrop trailer.

A 14KwH Tesla Powerwall 2.0 battery ($5500 including inverter) would run a 15 amp roof air conditioner for about 8 hours before going dead flat.

Then you'd have to generate 14+ KwH to recharge it. Tesla conservatively suggests a 5 Kw solar panel array, though you could get by with less if you restrict your usage to sunny days or supplement the charging with a generator. A 5 kw solar array is (50) 100 watt panels or (20) 250 watt panels, and so on. Plus a suitable charge controller.

There's nothing that can't be solved by throwing enough money at it. Except maybe finding enough real estate on the roof of the RV to hold the panels. Maybe set up multiple layers of panels you can unfold to make a king size patio awning?

Variable speed Fantastic Vents or equivalent draw far less power then an A/C unit (1watt to 18watts depending on speed setting) and are a good alternative for cooling a rig when off the grid. You could mount 1, 2, 3 of them in your roof as needed to keep the interior temperature down to about the ambient level.

All valid points. I know my friend only has to run his little window ac unit in his teardrop trailer for 5 minutes and the space inside his is like a meat locker. But I would rather have to run a generator and be able to stand up in my trailer than having to crawl into his. For him I know the inverter works but it is all due to the volume of the inside of the trailer and the very short amount of time it takes to cool it down. I was just really interested in seeing if anyone had done it without the generator. I really did think that it was impossible the way he was telling me to do it. And I certainly don't want to have to buy new batteries every few months due to discharging them so often using the inverter system since they cost so much. I will just run a generator and try to find places to camp where I am not around too many people or somewhere where everyone is using a generator. Thanks for all the input. I appreciate it. Mike

A number years ago I purchased a 115 watt solar panel, back then it was around $500.00 and a solar TriStar Charge controller another ~$150.00 and replaced the house battery under the door with three Costco RV type batteries.

Wired it all up and went boondocking for approx. 3 months in the Northwest Cascades.

My batteries could not be maintained using this solar / battery setup and running the geny was sort of cumbersome as if the batteries fall below or near 50 percent capacity it can take quite a while to get them full again. If fall extremely low potentially it can take days to recharge to full capacity. Then problems starts all over again where the three batteries become low or depleted. Plus if you in the wilderness to enjoy wildlife and nature listening to a geny run all day so to run a few 12 volt or possibly AC appliances isn't really imo very appealing.

I eventually gave up on the solar / geny and stopped using any electricity and the RV became more of shelter, i.e. a place to sleep.

For emergencies you should carry additional water, food, fuel, batteries, tools and at least a few supplies. Possibly a solar panel to charge small batteries._______________

From my experience boon docking in the Northwest my system should probably be a minimum 250 watt solar panels and at least twice or possibly more for battery storage.

I would need to try it again with an upgrade, such upgrade to 400 watt solar panels and a larger set of Trojan or possibly 6 volt golf cart batteries. However this can cost, be ready to spend at least $1500.00 for a new set of quality deep cycle batteries. The geny that came with the RV from the factory is a 4000 watt Onan, great generator however for only charging batteries I would prefer a quiet 1000 watt geny.

Or I could just keep it as it is and use the RV more as a shelter and forget about the electricity. Humans have lived a long time on this planet without electricity which hasn't historically been around very long compared to other things humans rely upon._____

My RV using the RV furnace and all the appliances did not benefit at all with this solar setup and the geny wasn't very good at keeping three RV batteries charged.

Things to consider in areas where there's not that much sunlight. Most RV furnaces are electricity hogs, mine runs a 7 amp fan that needs to turn on when starting, during operation and while stopping the RV furnace. LPG fumes need to be cleared when first starting and then stopping a RV furnace or the furnace won't operate.

I've since installed an additional Catalytic heater that doesn't require any electricity to run.

All the RV refrigerators I've looked at or owned require 12 volts to operate, when boondocking if you completely drain your batteries a RV refrigerator will stop working even though there's plenty of lpg.

RV refrigerators are normally are absorption refrigeration with a sealed network of tubes and chambers holding water, ammonia and hydrogen gas. A propane flame heats a chamber holding a solution of water and ammonia until the liquid boils. The ammonia gas rises to another chamber, the condenser, where it cools back into a liquid begins a cooling process.

This works great however absorption refrigerators are more expensive than an average home compressor frig and overall are usually more expensive to run as they require more energy for heat. Condenser motor refrigeration as you find in homes energywise usually cost less to run. Most of them now all have EPA energy ratings.Some people have tried switching over to an electric for when off-grid and boon docking however electricity is required to condense the refrigerant so a compressor frig may not be the best option when boon docking unless you have a frig designed for off-grid, solar, renewable energies using much less electricity.

We love our solar, have not had the generator out of truck in 2 years.... we do mostly boondocking.... BUT we have a 26' TT and I don't require a lot of extras when I am camping... No microwave, no AC, don't need that in Montana! ha.. but we did put on an 600 watt inverter in our new TT. Spent 30 days in the RV, I can charge my laptop, run the fan, and of course, we have a USB charge system built in our Cougar which charges all of our USB gizmo's. We only have a 150 watts Go Power solar on roof with controller to maintain our 2 6 volt batteries.... biggest issue I read about on here is people want their coffee pots plugged in... So far we are fine with the percolator and may go to a large french press.... But then again I am low maintenance... and don't require hair dryer, etc. figure we are clamping... with our King size bed and 32" TV. Now I have a new King Quest 4100 dome to put to the test this week on our solar and inverter... so we will see if I can run TV, receiver with our set up. I would be happy to just catch a program or two or news for a bit... The only real advantage that I see with hookups is that you can guarantee you WON'T hear any generators!!!